29/07/26 Bi-Weeky libp2p Spec Meeting

[johannamoran]

Attendees

@seetadev
@johannamoran
@richard-ramos nim-libp2p
@gmelodie nim-libp2p

Spec Lifecycle Stages

1. RFC [piloting]
2. Working Draft [POC in implement + Spec PR]
3. Candidate recommendation [ >2 implementations with interop recommended]
4. Recommendation [> 3 implementations and interop completed with applicable]

Agenda

WebRTC Direct V2 [Now at candidate recommendation]

Relevant Links

• [Summary] by lidel on WebRTC-Direct + Chrome changes (specs#672 comment at WebRTC-Direct: Chrome may be removing ICE credential munging #672 (comment) )
• [Spec PR Link] docs: webrtc-direct-v2 #715
• [Issue Link] WebRTC-Direct transport at risk due to Chrome changes (ICE credential munging): alignment and next steps go-libp2p#3499
• [js-libp2p PR Link] feat: webrtc-direct-v2 js-libp2p#3480
• [py-libp2p PR Link] feat(webrtc): add WebRTC transport scaffolding (spec compliance + tests) py-libp2p#1309 (comment)
• [go-libp2p Reference Link] feat(webrtc): stable /certhash across restarts go-libp2p#3512

UPDATE SINCE 07/07 Spec meeting

• WebRTC Direct V2 now in most recent versios of go-libp2p and py-libp2p

Next Steps

• Alignment with other libp2p maintainers to upgrade webRTC Direct V2 [dotnet, nim, zig, cpp, c]

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PQ at infrastructure level [RFC Stage]

• [Spec PR Link] docs: pkix #717
• [js-libp2p PR Link] feat: Post quantum identities with ML-DSA js-libp2p#3432

UPDATE SINCE 07/07 Spec meeting

• @seetadev identified the necessity to extend peer definitions to support both PQ and non-PQ simultaneously to avoid network fragmentation. This enhancement requires a coordinated effort, potentially involving the multi-formats working group and broader community discussions.
• @richard-ramos and @gmelodie expressed interest but noted the need to review specs in detail before review. The PQ at infrastructure initiative is seen as a complementary infrastructure layer with potential collaboration opportunities, especially for Nim’s security efforts.

Next Steps

• Nim team to review.

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[SECURITY] GossipSub Memory Exhaustion via Unbounded Remote Topic Subscriptions [RFC Stage]

• [Advisory Link 1] https://vulnerability.circl.lu/vuln/ghsa-4f8r-922h-2vgv
• [Advisory Link 2] GHSA-4f8r-922h-2vgv
• [cpp-libp2p PR Issue Link] Security: GossipSub Memory Exhaustion via Unbounded Remote Topic Subscriptions cpp-libp2p#349

UPDATE SINCE 07/07 Spec meeting

• Spec PR on memory exhaustion has been completed in c-libp2p and go-libp2p
• Plan to move this into candidate recommendation as this is implemented in cpp-libp2p, py-libp2p in progress

Next Steps

• @johannamoran to raise Spec PR

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Memory leak in clearPeerFromTopicsState retains empty topic maps indefinitely

• [Issue Link] Memory leak in clearPeerFromTopicsState retains empty topic maps indefinitely go-libp2p-pubsub#705

UPDATE SINCE 07/07 Spec meeting

• Clean up empty topic state maps go-libp2p-pubsub#708 [Complete and merged]

Next Steps

• @seetadev to coordinate follow-up discussions with Ethereum Prysm, Filecoin, and IPFS teams to clarify memory leak issues before raising the related spec PR

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datagrams: Add initial datagram draft (datagram that require acknowledgment)

[Spec PR] #680

UPDATE SINCE 07/07 Spec meeting

• @richard-ramos has reviewed and shared a lot of feedback.

Next Steps

• @gmelodie to review datagram spec PR and provide feedback

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gossipsub: add SPREAD extension spec

[Spec PR] #726

UPDATE SINCE 07/07 Spec meeting

• This is coming from the SSB network dao to researcher in GossipSub

Next Steps

@richard-ramos to review SPREAD pr in relation to the topic stream extensions

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New Spec PRs

Two new PRs announced: Encrypted Client Hello (ECH) and topic extensions for QUIC

###[TLS Handshake to enable support for RFC 9849: TLS Encrypted Client Hello] [link]

[Topic Streams Extension addition in Gossipsub: moves topic scoped application messages to separate long-lived streams] [link]

Next Steps

Nim team to review and comment on topic stream extensions PR and continue work on QUIC implementations with emphasis on ECH and multi-stream multiplexing

AOB

###Gossip Sub Interoperability and Testing
@seetadev noted that Improving Gossip Sub interoperability across implementations should be prioritized to ensure production readiness and spec progress and requested Nim’s team engage with Gossip Sub interoperability testing across Nim, Rust, Go, and Python implementations. Using shadow simulator approaches for GossipSub interop were discussed, noting shadow simulator limitations with QUIC connections.

Nim team plans to concentrate on Gossip Sub 1.1, widely used by Ethereum clients like Nimbus (Nim), Prism (Go) and Lighthouse (Rust). The goal is to ensure seamless peer discovery and communication in mixed-version and mixed-implementation networks. This foundational interop work will unlock further spec PRs and enhancements tailored for Ethereum-specific use cases.